1. Field of the Invention
The present invention relates to a cassette tape player, and particularly to a drive mechanism which moves, with a single motor, the cassette carrying mechanism which conveys a cassette tape in the player automatically and the mode selection lever which switches an operational mode of the player.
2. Description of the Prior Art
Cassette tape players for use in vehicles generally employ cassette carrying mechanisms. The cassette carrying mechanism automatically loads a cassette tape, which has been put halfway into the player, to the cassette hold position, and automatically ejects the cassette tape from the hold position. The cassette tape player further includes a reciprocating drive mechanism for moving a mode selection lever depending on the selected mode and a drive mechanism for rotating the reel bases in certain directions and at certain speeds depending on the mode.
All of these mechanisms are driven by a single motor by operation of idler gears provided between the motor and the drive mechanisms and associated electromagnetic solenoids which operate the idler gears. For example, at loading or ejecting a cassette tape, a solenoid operates on the idler gear between the motor and the cassette carrying mechanism to transmit the output torque of the motor to the cassette carrying mechanism.
However, a cassette carrying mechanism based on the operation of idler gears is likely to cause gear noise when an idler gear meshes with another gear in the transmission mechanism, and to fail to engage an idler gear with another gear due to faulty operational timing.
A drive mechanism that overcomes these problems is disclosed in U.S. Pat. No. 5,105,320. The cassette tape player disclosed therein is designed to keep the motor drive gear engage with the rack of the mode selection lever which is linked to the cassette carrying mechanism by a cam member. In operation, when the mode selection lever moves for a certain distance with the rotation of the Rotor, the cassette carrying mechanism performs the loading operation or ejecting operation through the cam member during the movement, and when the mode selection lever further moves an additional distance, another mechanism operates during the movement of the mode selection lever.
Although that conventional cassette tape player eliminates the gear noise and faulty gear meshing by retaining the motor drive gear in engagement with the rack of mode selection lever, the rack that is commonly used for moving the cassette carrying mechanism and other mechanisms must be very long, making the compact design of the cassette tape player difficult. Moreover, the cam member for driving the cassette carrying mechanism must be disposed between the mode selection lever-and the cassette carrying mechanism, resulting in a complex and costly mechanism.